This invention relates to devices and methods for cleaning an elongated record medium, and particularly to devices and methods for cleaning motion picture film.
In the cleaning of motion picture film, some of the problems that exist are that existing equipment and methods often are too slow, they often use too much expensive cleaning liquid, and sometimes they create noxious odors and emissions.
It is an object of this invention to eliminate or alleviate the foregoing problems.
More specifically, it is an object of the present invention to provide a cleaning device and method which cleans an elongated record medium such as motion picture film at a relatively high speed.
It is another object of the invention to provide such a device and method which utilizes relatively small quantities of cleaning liquid.
It is a further object of the invention to provide such a device and method which leave the record medium very clean and do not scratch or otherwise damage its surface.
It is an additional object of the invention to provide such a device and method in which the emission of fumes is greatly reduced or eliminated.
In accordance with the present invention, the foregoing objectives are met by the provision of a device and method in which a liquid solvent is sprayed onto the surface of the record medium, and then wiped off and the surface of the record medium is dried.
Preferably, the spray is a mist and the amount sprayed onto the film is relatively small. The record medium or film is dried by the use of a heated air stream.
It also is preferred that, prior to drying, thin jets of air are used to spread the liquid solvent on the surface of the motion picture film evenly, thereby avoiding streaking and spotting.
It also is preferred that the record medium or film be treated with a stream of ionized air to reduce or eliminate static electricity which might attract dirt and dust particles. The air stream preferably is heated to simultaneously dry and ionize the record medium.
Another preferred feature of the invention is the provision of a blower and vacuum combination which are used to clean dirt particles from the sprocket holes of motion picture film.
A further feature of the invention is the enclosure of the cleaning device in a closed housing, removing air from the housing through a vacuum system, and sending the solvent-laden air to a still to recover solvent. This arrangement not only reduces usage of the solvent, but it also greatly reduces or eliminates noxious odors and emissions from the cleaning device into the air surrounding it.
It also is preferred that the device used for wiping the film after it is sprayed is a rotary buffing wheel with a soft, replaceable velvet surface.
The foregoing and other objects and advantages of the invention are set forth in or will be apparent from the following descriptions and drawings.